Goals
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This section exists to organize files related to path functiontionality.  The path functionality standardizes movement, syncronization, branching, tagging, and general file maintainance inside the repository.

Description
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''CentOS like trees, has roots, trunk, branches, leaves and flowers.  Day by day they work together in freedom, ruled by the laws of nature and open standards, to show the beauty of its existence.''

Repository layout
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The repository layout describes organization of files and directories inside the repository. The repository layout provides the standard backend required for automation scripts to work correctly. If such layout changes unexpectedly, automation scripts may confuse themselves and stop doing what we expect from them to do.

As convenction, inside CentOS Artwork Repository, we organize files and directories related to CentOS corporate visual identity under three top level directories named: trunk/, branches/, and tags/.

Figure: The CentOS Artwork Repository layout.

The trunk/ directory (see trunk) organizes the main development line of CentOS corporate visual identity. Inside trunk/ directory structure, the CentOS corporate visual identity concepts are implemented using directories.  There is one directory level for each relevant concept inside the repository. The trunk/ directory structure is mainly used to perform development tasks related to CentOS corporate visual identity.

The branches/ directory (see branches) oranizes parallel development lines to trunk/ directory. The branches/ directory is used to set points in time where develpment lines are devided one from another taking separte and idependent lives that share a common past from the point they were devided on. The branches/ directory is mainly used to perform quality assurance tasks related to CentOS corporate visual identity.

The tags/ directory (see tags) organizes parallel frozen lines to branches/ directory.  The parallel frozen lines are immutable, nothing change inside them once they has been created.  The tags/ directory is mainly used to publish final releases of CentOS corporate visual identity.

The CentOS Artwork Repository layout is firmly grounded on a Subversion base.  Subversion (http://subversion.tigris.org) is a version control system, which allows you to keep old versions of files and directories (usually source code), keep a log of who, when, and why changes occurred, etc., like CVS, RCS or SCCS.  Subversion keeps a single copy of the master sources.  This copy  is called the source ``repository''; it contains all the information to permit extracting previous versions of those files at any time.

Repository name convenctions
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Repository name convenctions help us to maintain consistency of names inside the repository.

Repository name convenctions are applied to files and directories inside the repository layout. As convenction, inside the repository layout, file names are all written in lowercase (01-welcome.png, splash.png, anaconda_header.png, etc.) and directory names are all written capitalized (e.g., Identity, Themes, Motifs, TreeFlower, etc.).

Repository name convenctions are implemented inside the cli_getRepoName function of centos-art.sh script. With cli_getRepoName function we reduce the amount of commands and convenctions to remember, concentrating them in just one single place to look for fixes and improvements.

Repository work flow
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Repository work flow describes the steps and time intervals used to produce CentOS corporate visual identity inside CentOS Artwork Repository.

To illustrate repository work flow let's consider themes' development cycle.

Initially, we start working themes on their trunk development line (e.g., trunk/Identity/Themes/Motifs/TreeFlower/), here we organize information that cannot be produced automatically (i.e., background images, concepts, color information, screenshots, etc.).

Later, when theme trunk development line is considered ``ready'' for implementation (e.g.,  all required backgrounds have been designed), we create a branch for it (e.g., branches/Identity/Themes/Motifs/TreeFlower/1/).  Once the branch has been created, we forget that branch and continue working the trunk development line while others (e.g., an artwork quality assurance team) test the new branch for tunning it up.

Once the branch has been tunned up, and considered ``ready'' for release, it is freezed under tags/ directory (e.g., tags/Identity/Themes/Motifs/TreeFower/1.0/) for packagers, webmasters, promoters, and anyone who needs images from that CentOS theme the tag was created for.

Both branches and tags, inside CentOS Artwork Repository, use numerical values to identify themselves under the same location. Branches start at one (i.e., 1) and increment one unit for each branch created from the same trunk development line.  Tags start at zero (i.e., 0) and increment one unit for each tag created from the same branch development line.

Figure: Name convention for tags and branches creation.

     Convenction Do not freeze trunk development lines using tags directly.  If you think you need to freeze a trunk development line, create a branch for it and then freeze that branch instead.

The trunk development line may introduce problems we cannot see immediatly. Certainly, the high changable nature of trunk development line complicates finding and fixing such problems. On the other hand, the branched development lines provide a more predictable area where only fixes/corrections to current content are commited up to repository.

If others find and fix bugs inside the branched development line, we could merge such changes/experiences back to trunk development line (not visversa) in order for future branches, created from trunk, to benefit.

Time intervals used to create branches and tags may vary, just as different needs may arrive. For example, consider the release schema of CentOS distribution: one major release every 2 years, security updates every 6 months, support for 7 years long. Each time a CentOS distribution is released, specially if it is a major release, there is a theme need in order to cover CentOS distribution artwork requirements. At this point, is where CentOS Artwork Repository comes up to scene.

Before releasing a new major release of CentOS distribution we create a branch for one of several theme development lines available inside the CentOS Artwork Repository, perform quality assurance on it, and later, freeze that branch using tags. Once a the theme branch has been frozen (under tags/ directory), CentOS Packagers (the persons whom build CentOS distribution) can use that frozen branch as source location to fulfill CentOS distribution artwork needs. The same applies to CentOS Webmasters (the persons whom build CentOS websites), and any other visual manifestation required by the project.

Parallel directories
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Inside CentOS Artwork Repository, parallel directories are simple directory entries built from a common parent directory and placed in a location different to that, the common parent directory is placed on. Parallel directories are useful to create branches, tags, translations, documentation, pre-rendering configuration script, and similar directory structures.

Parallel directories take their structure from one unique parent directory. Inside CentOS Artwork Repository, this unique parent directory is under trunk/Identity location.  The trunk/Identity location must be considered the reference for whatever information you plan to create inside the repository.

In some circumstances, parallel directories may be created removing uncommon information from their paths. Uncommon path information refers to those directory levels in the path which are not common for other parallel directories.  For example, when rendering trunk/Identity/Themes/Motifs/TreeFlower/Distro directory structure, the centos-art.sh script removes the Motifs/TreeFlower/ directory levels from path, in order to build the parallel directory used to retrived translations, and pre-rendering configuration scripts required by render functionality.

Figure: Parallel directories removing uncommon information.

Another example of parallel directory is the documentation structure created by manual functionality. This time, centos-art.sh script uses parallel directory information with uncommon directory levels to build the documentation entry required by Texinfo documentation system, inside the repository.

Othertimes, parallel directories may add uncommon information to their paths. This is the case we use to create branches and tags. When we create branches and tags, a numerical identifier is added to parallel directory structure path. The place where the numerical identifier is set on is relevant to corporate visual identity structure and should be carefully considered where it will be.

Figure: Parallel directories adding uncommon information.

When one parent directory changes, all their related parallel directories need to be changed too. This is required in order for parallel directories to retain their relation with the parent directory structure.  In the other hand, parallel directories should never be modified under no reason but to satisfy the relation to their parent directory structure.  Liberal change of parallel directories may suppresses the conceptual idea they were initially created for; and certainly, things may stop working the way they should do.

Figure: Wrong construction of parallel directories.

Syncronizing path information
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Parallel directories are very useful to keep repository organized but introduce some complications.  For instance, consider what would happen to functionalities like manual (trunk Scripts Bash Functions Manual) that rely on parent directory structures to create documentation entries (using parallel directory structures) if one of those parent directory structures suddenly changes after the documentation entry has been already created for it?

In such cases, functionalities like manual may confuse themselves if path information is not updated to reflect the relation with its parent directory.  Such functionalities work with parent directory structure as reference; if a parent directory changes, the functionalities dont't even note it because they work with the last parent directory structure available in the repository, no matter what it is.

In the specific case of documentation (the manual functionality), the problem mentioned above provokes that older parent directories, already documented, remain inside documentation directory structures as long as you get your hands into the documentation directory structure (trunk/Manuals) and change what must be changed to match the new parent directory structure.

There is no immediate way for manual, and similar functionalities that use parent directories as reference, to know when and how directory movements take place inside the repository. Such information is available only when the file movement itself takes place inside the repository. So, is there, at the moment of moving files, when we need to syncronize parallel directories with their unique parent directory structure.

     Warning There is not support for URL reference inside centos-art.sh script.  The centos-art.sh script is designed to work with local files inside the working copy only.

As CentOS Artwork Repository is built over a version control system, file movements inside the repository are considered repository changes. In order for these repository changes to be versioned, we need to, firstly, add changes into the version control system, commit them, and later, perform movement actions using version control system commands. This configuration makes possible for everyone to know about changes details inside the repository; and if needed, revert or update them back to a previous revision.

Finally, once all path information has been corrected, it is time to take care of information inside the files. For instance, considere what would happen if you make a reference to a documentation node, and later the documentation node you refere to is deleted. That would make Texinfo to produce error messages at export time. So, the centos-art.sh script needs to know when such changes happen, in a way they could be noted and handled without producing errors.

What is the right place to store it?
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Occasionly, you may find that new corporate visual identity components need to be added to the repository. If that is your case, the first question you need to ask yourself, before start to create directories blindly all over, is: What is the right place to store it?

The CentOS Community different free support vains (see: http://wiki.centos.org/GettingHelp) are the best place to find answers to your question, but going there with hands empty is not good idea. It may give the impression you don't really care about. Instead, consider the following suggestions to find your own comprehension and so, make your propositions based on it.

When we are looking for the correct place to store new files, to bear in mind the corporate visual identity structure used inside the CentOS Artwork Repository (see trunk Identity) would be probaly the best advice we could offer, the rest is just matter of choosing appropriate names.  To illustrate this desition process let's consider the trunk/Identity/Themes/Motifs/TreeFlower directory as example. It is the trunk development line of TreeFlower artistic motif. Artistic motifs are considered part of themes, which in turn are considered part of CentOS corporate visual identity.

When building parent directory structures, you may find that reaching an acceptable location may take some time, and as it uses to happen most of time; once you've find it, that may be not a definite solution.  There are many concepts that you need to play with, in order to find a result that match the conceptual idea you try to implement in the new directory location. To know which these concepts are, split the location in words and read its documentation entry from less specific to more specific.

For example, the trunk/Identity/Themes/Motifs/TreeFlower location evolved through several months of contant work and there is no certain it won't change in the future, even it fixes quite well the concept we are trying to implement.  The concepts used in trunk/Identity/Themes/Distro/Motifs/TreeFlower location are described in the following commands, respectively:

centos-art manual --read=turnk/
centos-art manual --read=turnk/Identity/
centos-art manual --read=turnk/Identity/Themes/
centos-art manual --read=turnk/Identity/Themes/Motifs/
centos-art manual --read=turnk/Identity/Themes/Motifs/TreeFlower/

Other location concepts can be found similary as we did above, just change the location we used above by the one you are trying to know concepts for.

Usage
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centos-art path --copy='SRC' --to='DST'

     Copy SRC to DST and schedule DST for addition (with history).  In this command, SRC and DST are both working copy (WC) entries.

centos-art path --delete='SRC'

     Delete DST. In order for this command to work the file or directory you intend to delete should be under version control first. In this command, SRC is a working copy (WC) entry.

See also
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